The doctor's chartered plane was carrying advanced medical equipment not available in Cuba when it left Thursday, the newspaper reported.

Officials at Madrid's Gregorio Maranon Hospital, where Garcia Sabrido is head of surgery, declined to comment, as did the Cuban Embassy in Madrid.

Garcia Sabrido was among doctors who presented their work at a surgery conference in Havana last month, according to the conference's website.

Cuban officials say Castro is not dying and will return to public life. But he has skipped recent public appearances, including a belated celebration of his 80th birthday, and appeared to be frail and walking with difficulty in video released in October.